Dear Subba Rao,

Your question is relevant and requires lengthy debate. This space will not be enough to discuss at length on the subject. But here are some thoughts.

Agriculture must literally go back to its roots by rediscovering the importance of healthy soil, using natural sources of plant nutrition, and using mineral fertilizer wisely.

How mineral fertilizers affect the environment is a management matter. For example, calculate the ratio between the amount of fertilizer applied and the one that was extracted by crops, or it is necessary to optimize the method and timing of fertilizer applications. In other words, it is the efficiency of the use of fertilizers, particularly nitrogen and phosphorus (P), which determines if this aspect of soil management is good for crops or if it has negative effects on the environment.

The challenge is therefore to give up unsustainable agricultural practices and to choose options that can provide a solid basis for sustainable crop intensification. In many countries, it should overhaul land management methods. The new approaches advocated in this comment, which are based on the work undertaken by the FAO and many other institutions, focus on the management of soil health.

The following measures should be taken to improve the current practices of land management and to lay the necessary foundation for sustainable crop intensification. It is national partners must take the initiative, with the support of FAO and other international bodies.

1. Establish national regulations for proper land management. A package of favorable measures should encourage farmers to adopt sustainable farming systems, based on healthy soils. Command capabilities are required to establish and monitor best practices, with the active participation of small farmers and their communities. As for governments, they must be prepared to regulate farming practices that cause soil degradation and pose a serious threat to the environment.

2. Monitoring of soil health. Policymakers and national institutions responsible for the environment need tools and methods to check the effects of agricultural practices. The monitoring soil health is a very difficult task, but efforts are underway to execute globally, regionally and nationally. Monitor the effects of agricultural production has increased significantly in developed countries but in many developing countries, this activity is still in its infancy. FAO and its partners have established a list of methods and tools that can be used for carrying out assessments and monitoring. It should distinguish the basic indicators of soil quality, requiring immediate or long-term development. The priority indicators are the content of organic matter in soil, the balance between different nutrients, yield spreads, land use intensity and diversity and finally land cover. The indicators that have yet to be developed refer to the quality of soil, degradation of land and agricultural biodiversity.

3. Capacity building. The soil health management can not be achieved without extensive knowledge and its wide adoption will require capacity building through training programs for extension workers and farmers. It will also build the capacity of researchers, both nationally and internationally, to generate additional knowledge to support improved land management in the context of sustainable crop intensification. Policy makers should consider new approaches, such as support groups for cooperation in search of adaptation, which provide technical support and on-the-job training for national research institutes, and transform the practice in search results for small farmers. It will strengthen national capacity to undertake research at the farm level, focusing on the spatial and temporal variability, for example by making greater use ecosystem modelling.

4. Dissemination of information and sharing of useful elements. To manage the health of large-scale land requires that the necessary information is widely available, including through networks with which farmers and extension workers are familiar. Given the very high priority attached to soil health in sustainable crop intensification, the media used should include not only national newspapers and radio programs, as well as modern information technologies and communication, as the mobile phone and the internet, which are far more effective ways to reach young farmers.

Wth my best regards

Prof. Bachir ACHOUR

To put it simply, soil compaction, deep root removal, tillage, synthetic fertilizers, insecticides, fungicides, and herbicides all damage the soil by reducing air pore size, altering drainage, erosion, eliminating healthy populations of mycorrhizae and beneficial worms, insects and bacteria, as well as providing a good environment for pest species to thrive without natural competition.

The answer is a reduction of tillage and an abandonment of the mono-culture form of agriculture that will result in a reduced need to use agricultural chemicals. The development of more perfected composting methods and the extraction and sterilization of compost tea will provide good alternatives to the current use of nitrates and phosphates as fertilizer. Greenhouse cultivation also eliminates detrimental effects on the soil and environment by reducing interactions with the soil and providing a physical barrier to elements that require chemical control outside.

Degradation of soil texture (plowing), destruction of useful microorganisms (chemical products), undesirable genetic mutation ........................... .................................................. .......... The human and animal health is directly affected by agricultural products not naturale.

Dear colleagues ,we got three responses which  provide the backdrop for the topic often discussed ,relevant  in the present context and which may provide leads to future agriculture.The dominant features of current intensive agriculture are mono culture,continuous cropping, new seed varieties,conventional tillage, cultivation even on sloppy lands,intensive stock systems,often away from agricultural fields,use of imbalanced fertilizers from low to very high amounts,pesticides use, moderate to heavy irrigation and processing the produce generates waste.Mono culture with high yielding varieties of limited number of crops not only reduce biodiversity of crops but also insects and other beneficial organisms necessitating use more pesticides.Continuous cropping without break or fallow may exhaust soil nutrients as all nutrients can not be replaced through fertilizer or manure.Conventional tillage may accelerate decomposition of soil organic matter and contributes to CO2 in the environment .Cultivation on sloppy lands leads to loss of soil,  water and nutrients.Livestock enterprises contribute to methane emissions and the dung produced may lead to nitrate leaching or N2O emission .Fertilizers use is an essential component in intensive agriculture Excess use of N may lead to NO3 leaching and ground water pollution and N2O emission may contribute to global warming Excess P fertilizer use may accumulate P in soil and subjected to erosion losses and contamination of nearby ware body.Pesticide residues in soil and water will affect animal and human health,Excess irrigation may deplete under ground water resources and also cause waterlogging and salinization. Crop produce processing  requires energy and also generates waste which needs to be used  for economic benefits and reduce pollution.I tried to put in perspective many of the issues .I request colleagues to deal aspects of their interest and give valuable views with focus on best practices to follow and corrections needed.

It is now well known that modern agricultural practices have a trade-offs in terms of their impact on environment, biodiversity and livelihoods.Agronomists world over are abreast with these issues and a lot of good research is happening. However, there is now a need to put in place several bits and pieces of research findings and arrive at some successful models of systems which address the 3 Es- economics, environment and equity. Connecting such integrated systems with value-chains to address livelihoods issues will be eminently useful. Research can be compartmentalized but solutions for common problems require more comprehensive and integrated efforts-across research, policy and governance.

Dr.Prakasa Rao and other colleagues,some effects of conventional agricultural practices have become clear and organizations like FAO are playing lead role(details as given by as Dr.Achour) in assessing, monitoring and correcting the practices.Many governments are implementing soil health programmes.  especiallin developing countries.How ever, some issues related to machinery use ( soil compaction),varieties  and monoculture(biodiversity loss) ,irrigation(water table depletion and water logging )pesticides use(some 1000 major agricultural pests are resistant to pesticides) .cultivation practices( conservation agriculture vers .conventional cultivation). integrating livestock and agriculture enterprises, waste utilization,water pollution etc are not properly addressed and necessary remedial measures/best practices are not being followed.To intervene and correct/modify the practices we need some meta analysis pooling data from similar  or across globe of the practices and their real effects.After knowing the  magnitude of problem in each aspect one can go for interventions.

HI,Stop using banned pesticides for agriculture or to reduce pest of all variety.Follow ancient practises of making a compost of dried leaves,cowdung and vegetable peels.Construct  canals and water bed for irrigation.start rain harvesting programme in every household in india.not to use genetically modified seeds and sapplings,which one or other way creating more menance to environment,although increase the productivity and utility.for example in KERALA ,ALUWA railwaystation,india,uses pet waterbottles thrown by passengers to make hanging garden,Encourage terrace garden practises,unless and untill we change our pattern of agriculture,the same pollution problem will persist

In India, we have tried to put together available data on the issue of nitrate pollution, especially in agro- ecosystems and suggested remedial and policy measures. I agree with Dr. Subba Rao that we need meta analyses of  polluting factors in agro-ecosystems.

ref:

1.      Prakasa Rao, E.V.S. and K. Puttanna (2000).  Nitrates, agriculture and environment.   Curr. Sci. 79(9): 1163-1168.

2. Prakasa Rao, E.V.S. and Puttanna, K. (2006).  Strategies for combating nitrate   pollution.  Curr. Sci. 91(10), 1335-1339. 

3. Bijay Singh, E.V.S.Prakasa Rao, Yadvinder Singh and K. Puttanna (2007).  Nitrate pollution of ground water vis-à-vis nitrogen fertilizer use in India.  Agricultural Nitrogen Use and its Environmental Implications (Eds.) Y.P.Abrol, N. Raghuram and M.S.Sachdev ,  I.K.Intern.Pub.House Pvt.Ltd., New Delhi,pp. 439-458.439-458.

4. Gupta Sunil, Gupta R.C., Gupta A.B., Eskiocak Sevgi, Prakasa Rao E.V.S.,        Puttanna K. and Singhvi Aditi (2010) Pathophysiology of Nitrate  Toxicity in Human       and its Mitigation Measures, In ING Bulletins on Regional Assessment of Reactive  Nitrogen, Bulletin No. 20, (Ed. N. Raghuram),SCON-ING, New Delhi, pp i-iv &1-78.

Dr. Subba Rao, you raised a very good topic for discussion. Modern agriculture system need to be checked. Our agricultural out put demand is more and more and soil is degrading very fast. As to full fill the demand, best option looks Application of fertilisers. Mostly people not aware about the selective and optimum level of these. Pesticide and insecticide are other problem. Mostly insecticides are insoluble in water. Ground waters are being contaminated which result to degrade the soil structure and production by quality and quantity based. For example in some part of India, Rice is being contaminated by arsenic. Thus aware ness is very much required. Appreciated forsuch a very useful topic.

It depends upon the country to begin with. Those countries who's agricultural practices are limited in the sense of little or no usage of pesticides/herbicides/fertilizers who are subsistence in nature cause less impact on the quality of soils and water resources. Those nations who rely heavily on pesticides/herbicides/fertilizers can and do have a major impact on soil and water quality issues.